The present invention relates to a filter apparatus, particularly to filter housings and filter housing components for filtering intake air for internal combustion engines and other uses where a filtered, particulate free clean air source is beneficial. Air filter elements and filter housings are known in the art, and as particularly related to this application, filter apparatus are known having generally cylindrical housing including a tangential or alternately radial inlet fitting secured onto a side of the housing and an outlet fitting secured to an axial end of the housing.
U.S. Pat. No. 5,882,367 discloses a filter apparatus in which a filter cartridge is disposed in a substantially cylindrical housing. On the lateral surface of the filter housing, an inlet opening is provided which communicates with an annular space formed between the filter cartridge and the housing. Within the filter cartridge, a chamber is formed from which the filtered air is discharged through an outlet fitting. The outlet fitting is secured in a snap-in relation to an axial end face of the housing by a “V” shaped retention feature. An “O” ring seal is provided between the outlet fitting and the filter housing.
U.S. Published Patent Application 2007/0284301 discloses a filter apparatus including a housing and a filter insert with an inlet opening formed on the housing and an outlet fitting mounted on a housing wall. The outlet fitting has a contact face for contact with the housing and is provided with a tubular segment, which protrudes through an opening of the housing. A mounting element is attached to the tubular segment such that a region of the housing surrounding the opening is clamped between the contact face of the outlet fitting and the mounting element.
In known filter housings that are provided with an axial outlet fitting or tube mounted to the filter housing in a snap-in relation, the outlet fitting remains rotatable relative to the housing after snap-in installation. In certain applications the geometry and layout of nearby and connecting components in the final installation typically dictate the required rotational position of the outlet fitting on the filter housing and therefore, rotation of the outlet fitting during shipping or installation is undesirable. Additionally, engine vibration can lead to an undesirable rotation of the outlet fitting relative to the housing during vehicle operation. This can lead to a potential decoupling of the engine clean air intake piping from the outlet fitting, compromising required engine intake air filtration.